The Hetch Hetchy Reservoir, located in Yosemite National Park, has had the attention of many these past several years but more intensely at present. Indeed, the citizenry of San Francisco will have the opportunity to consider the future of this facility by their vote on an advisory ballot measure on Tuesday.

The ultimate removal of the reservoir would make possible the restoration of Hetch Hetchy Valley a few miles from Yosemite Valley and, amazingly, a near twin of that extraordinary gift of nature. The very glacial action that formed Yosemite Valley created Hetch Hetchy Valley as well.

In coming to a sound conclusion as to restoration of Hetch Hetchy to make available to all another Yosemite, we should understand how things got this way.

Prior to the turn of the century, public policy at the national as well as the state level promoted population growth in the mid-West and far West. Thus, governmental action made vast federal lands available to those who would farm certain acreage and undertook construction of far-reaching water facilities. In addition, local cities such as San Francisco and Los Angeles were given the necessary permission to utilize public lands and water resources to provide water for their growth. San Francisco got permission to build O'Shaughnessy Dam in Yosemite National Park! And the dam, completed in 1923, has served the citizens of San Francisco and neighboring Bay Area cities well.

Similarly, the city of Los Angeles sought and obtained federal government approval for its water facilities at Mono Lake and related areas. This allowed diversion of streams that would otherwise flow into the saline lake to instead feed the city's water delivery system. Because the system relied on gravity flows, substantial electrical power, worth many millions, was produced, similar to the electricity production on San Francisco's aqueduct system.

Many years later, local government supported by environmental

organizations and many of the citizens of Los Angeles agreed to restriction of the Los Angeles water diversions and corresponding loss of electricity production.

The substantial modification of Los Angeles' Mono Lake rights and the current proposed restoration of Hetch Hetchy Valley, along with changes or proposed changes in a number of water project operations in California and other states, illustrate something far greater than these specific projects.

We have no less than a major change in public policy that has prevailed for the last hundred years. In large part, due to various litigation and educational and political activities of public interest environmental organizations, we no longer consider the natural environment merely as a grand resource to be exploited for agricultural and urban uses. The natural environment, as such, has great value.

In California, the federal court has restricted the water that may be diverted from the Sacramento-San Joaquin Delta for agricultural and urban uses, having found that the level of diversion was harmful to the Delta smelt. And plans are under way to remove dams on the Klamath River in Oregon to allow salmon once again to swim upstream for spawning. In short, the public is taking another look at how the natural environment has been utilized, and, in many cases, has changed its mind as to how the environment should be treated.

What are the relevant considerations for modifying water projects and operations which have resulted, as intended, in the growth of cities and establishment of farms? This turns on careful consideration of what alternatives are available, their costs, and costs of the environmental restoration versus the value of the environmental goal to be achieved.

The Los Angeles public and ultimately its political representatives believed Mono Lake warranted restoration and have paid the cost, albeit with financial assistance from the federal government, of purchasing water and utilizing an alternate source for the loss of the electricity production.

In the case of Hetch Hetchy, it isn't that San Francisco's water supply now stored at the O'Shaughnessy Dam will be lost. Rather, it would be stored at existing dams downstream and perhaps offstream or in groundwater basins. These and other aspects of the proposed removal have been studied but without involvement of city officials.

San Franciscans who support the ballot measure will be asking their city to consider modification of their water delivery system for the benefit of the environment - something Los Angelinos have already accomplished. It's a responsible approach for pursuing the potential of recreating another Yosemite Valley and its success would validate John Muir's heroic fight to preserve Hetch Hetchy Valley.

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